Nowadays the use of laundry washing machines, both “simple” laundry washing machines (i.e. laundry washing machines which can only wash and rinse laundry) and laundry washing and drying machines (i.e. laundry washing machines which can also dry laundry), is widespread.
In the present description the term “laundry washing machine” will refer to both simple laundry washing machines and laundry washing and drying machines.
In addition, in the present description when reference is made to “water”, the term “water” may denote water as such, washing water, washing liquid, washing liquor or the like.
As it is known, a laundry washing machine comprises a water tub to receive water and a cylindrical rotary drum rotatably mounted in the water tub to receive laundry, which washes the laundry by lifting and dropping the laundry in the rotary drum along the inner surface of the rotary drum during the rotation of the rotary drum.
During a wash phase, the laundry washing machine determines the amount of wash water and rinse water according to a user's selection of a washing course, supplies water such as wash water having an amount sufficient to wash the laundry, supplies detergent into the water tub according to the determined amount of wash water, and performs washing operations while detergent and water are forwarded to the laundry and the laundry is dropped by the rotation of the rotary drum.
At the end of the wash phase, the laundry washing machine generally performs one or more washing intermediate spins wherein the drum is rotated at a high speed one or more times for extracting washing water from the laundry; during and/or after these washing intermediate spins water is drained from the washing tub by activating a draining pump.
Afterwards the washing machine starts the rising phase wherein supplies water having an amount sufficient to rinse the laundry into the water tub according to the determined amount of rinse water, and performs a rinsing operation while water is brought into contact with the laundry and the laundry is dropped by the rotation of the rotary drum.
At the end of the rinse phase, the laundry washing machine performs one or more rinsing intermediate spins, substantially in the same manner as the above described washing operation, and the drainage of the dirty water.
Generally, laundry washing machine comprises an electronic control system which is configured to perform or alternately skip the intermediate spins during the wash or rinse phases, based on the results of preset machine checks that electronic control system performs before implementing intermediate spins.
In detail, electronic control system is usually configured to skip washing or rinsing intermediate spins, when it detects, immediately before implementing spins, that laundry load is unbalanced and/or high quantity of foam is formed in the rotary drum.
Tests made by the applicant proved that intermediate spins are most skipped with full laundry loads and/or sponge laundries and that skipping intermediate spins causes high quantity of dirty water to remain inside the laundry.
Accordingly, if washing or rinsing intermediate spins are skipped, there is the risk that dirty washing/rinsing liquid is not effectively removed from the laundry before the following rinsing phase, which can worsen the rinsing performances of the following rinsing step.
The applicant conducted an in-depth study with the objective of identifying a solution which specifically allows keeping constant the rinse performance of the cycle even if intermediate spin are skipped or modified.
It is thus the object of the present invention to provide a solution which allows achieving the objective indicated above.